libvpx: Pull from upstream

source/libvpx/vp9/decoder/vp9_dthread.c

Index: source/libvpx/vp9/decoder/vp9_dthread.c
===================================================================
--- source/libvpx/vp9/decoder/vp9_dthread.c	(revision 0)
+++ source/libvpx/vp9/decoder/vp9_dthread.c	(revision 0)
@@ -0,0 +1,272 @@
+/*
+ *  Copyright (c) 2014 The WebM project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "./vpx_config.h"
+#include "vp9/common/vp9_reconinter.h"
+#include "vp9/decoder/vp9_dthread.h"
+#include "vp9/decoder/vp9_onyxd_int.h"
+#include "vpx_mem/vpx_mem.h"
+
+#if CONFIG_MULTITHREAD
+static INLINE void mutex_lock(pthread_mutex_t *const mutex) {
+  const int kMaxTryLocks = 4000;
+  int locked = 0;
+  int i;
+
+  for (i = 0; i < kMaxTryLocks; ++i) {
+    if (!pthread_mutex_trylock(mutex)) {
+      locked = 1;
+      break;
+    }
+  }
+
+  if (!locked)
+    pthread_mutex_lock(mutex);
+}
+#endif  // CONFIG_MULTITHREAD
+
+static INLINE void sync_read(VP9LfSync *const lf_sync, int r, int c) {
+#if CONFIG_MULTITHREAD
+  const int nsync = lf_sync->sync_range;
+
+  if (r && !(c & (nsync - 1))) {
+    mutex_lock(&lf_sync->mutex_[r - 1]);
+
+    while (c > lf_sync->cur_sb_col[r - 1] - nsync) {
+      pthread_cond_wait(&lf_sync->cond_[r - 1],
+                        &lf_sync->mutex_[r - 1]);
+    }
+    pthread_mutex_unlock(&lf_sync->mutex_[r - 1]);
+  }
+#else
+  (void)lf_sync;
+  (void)r;
+  (void)c;
+#endif  // CONFIG_MULTITHREAD
+}
+
+static INLINE void sync_write(VP9LfSync *const lf_sync, int r, int c,
+                              const int sb_cols) {
+#if CONFIG_MULTITHREAD
+  const int nsync = lf_sync->sync_range;
+  int cur;
+  // Only signal when there are enough filtered SB for next row to run.
+  int sig = 1;
+
+  if (c < sb_cols - 1) {
+    cur = c;
+    if (c % nsync)
+      sig = 0;
+  } else {
+    cur = sb_cols + nsync;
+  }
+
+  if (sig) {
+    mutex_lock(&lf_sync->mutex_[r]);
+
+    lf_sync->cur_sb_col[r] = cur;
+
+    pthread_cond_signal(&lf_sync->cond_[r]);
+    pthread_mutex_unlock(&lf_sync->mutex_[r]);
+  }
+#else
+  (void)lf_sync;
+  (void)r;
+  (void)c;
+  (void)sb_cols;
+#endif  // CONFIG_MULTITHREAD
+}
+
+// Implement row loopfiltering for each thread.
+static void loop_filter_rows_mt(const YV12_BUFFER_CONFIG *const frame_buffer,
+                                VP9_COMMON *const cm, MACROBLOCKD *const xd,
+                                int start, int stop, int y_only,
+                                VP9LfSync *const lf_sync, int num_lf_workers) {
+  const int num_planes = y_only ? 1 : MAX_MB_PLANE;
+  int r, c;  // SB row and col
+  LOOP_FILTER_MASK lfm;
+  const int sb_cols = mi_cols_aligned_to_sb(cm->mi_cols) >> MI_BLOCK_SIZE_LOG2;
+
+  for (r = start; r < stop; r += num_lf_workers) {
+    const int mi_row = r << MI_BLOCK_SIZE_LOG2;
+    MODE_INFO **mi_8x8 = cm->mi_grid_visible + mi_row * cm->mode_info_stride;
+
+    for (c = 0; c < sb_cols; ++c) {
+      const int mi_col = c << MI_BLOCK_SIZE_LOG2;
+      int plane;
+
+      sync_read(lf_sync, r, c);
+
+      setup_dst_planes(xd, frame_buffer, mi_row, mi_col);
+      vp9_setup_mask(cm, mi_row, mi_col, mi_8x8 + mi_col, cm->mode_info_stride,
+                     &lfm);
+
+      for (plane = 0; plane < num_planes; ++plane) {
+        vp9_filter_block_plane(cm, &xd->plane[plane], mi_row, &lfm);
+      }
+
+      sync_write(lf_sync, r, c, sb_cols);
+    }
+  }
+}
+
+// Row-based multi-threaded loopfilter hook
+static int loop_filter_row_worker(void *arg1, void *arg2) {
+  TileWorkerData *const tile_data = (TileWorkerData*)arg1;
+  LFWorkerData *const lf_data = &tile_data->lfdata;
+
+  loop_filter_rows_mt(lf_data->frame_buffer, lf_data->cm, &lf_data->xd,
+                      lf_data->start, lf_data->stop, lf_data->y_only,
+                      lf_data->lf_sync, lf_data->num_lf_workers);
+  return 1;
+}
+
+// VP9 decoder: Implement multi-threaded loopfilter that uses the tile
+// threads.
+void vp9_loop_filter_frame_mt(VP9D_COMP *pbi,
+                              VP9_COMMON *cm,
+                              MACROBLOCKD *xd,
+                              int frame_filter_level,
+                              int y_only, int partial_frame) {
+  // Number of superblock rows and cols
+  const int sb_rows = mi_cols_aligned_to_sb(cm->mi_rows) >> MI_BLOCK_SIZE_LOG2;
+  int i;
+
+  // Allocate memory used in thread synchronization.
+  // This always needs to be done even if frame_filter_level is 0.
+  if (!cm->current_video_frame || cm->last_height != cm->height) {
+    VP9LfSync *const lf_sync = &pbi->lf_row_sync;
+
+    if (cm->last_height != cm->height) {
+      const int aligned_last_height =
+          ALIGN_POWER_OF_TWO(cm->last_height, MI_SIZE_LOG2);
+      const int last_sb_rows =
+          mi_cols_aligned_to_sb(aligned_last_height >> MI_SIZE_LOG2) >>
+          MI_BLOCK_SIZE_LOG2;
+
+      vp9_loop_filter_dealloc(lf_sync, last_sb_rows);
+    }
+
+    vp9_loop_filter_alloc(cm, lf_sync, sb_rows, cm->width);
+  }
+
+  if (!frame_filter_level) return;
+
+  vp9_loop_filter_frame_init(cm, frame_filter_level);
+
+  // Initialize cur_sb_col to -1 for all SB rows.
+  vpx_memset(pbi->lf_row_sync.cur_sb_col, -1,
+             sizeof(*pbi->lf_row_sync.cur_sb_col) * sb_rows);
+
+  // Set up loopfilter thread data.
+  for (i = 0; i < pbi->num_tile_workers; ++i) {
+    VP9Worker *const worker = &pbi->tile_workers[i];
+    TileWorkerData *const tile_data = (TileWorkerData*)worker->data1;
+    LFWorkerData *const lf_data = &tile_data->lfdata;
+
+    worker->hook = (VP9WorkerHook)loop_filter_row_worker;
+
+    // Loopfilter data
+    lf_data->frame_buffer = get_frame_new_buffer(cm);
+    lf_data->cm = cm;
+    lf_data->xd = pbi->mb;
+    lf_data->start = i;
+    lf_data->stop = sb_rows;
+    lf_data->y_only = y_only;   // always do all planes in decoder
+
+    lf_data->lf_sync = &pbi->lf_row_sync;
+    lf_data->num_lf_workers = pbi->num_tile_workers;
+
+    // Start loopfiltering
+    if (i == pbi->num_tile_workers - 1) {
+      vp9_worker_execute(worker);
+    } else {
+      vp9_worker_launch(worker);
+    }
+  }
+
+  // Wait till all rows are finished
+  for (i = 0; i < pbi->num_tile_workers; ++i) {
+    vp9_worker_sync(&pbi->tile_workers[i]);
+  }
+}
+
+// Set up nsync by width.
+static int get_sync_range(int width) {
+  // nsync numbers are picked by testing. For example, for 4k
+  // video, using 4 gives best performance.
+  if (width < 640)
+    return 1;
+  else if (width <= 1280)
+    return 2;
+  else if (width <= 4096)
+    return 4;
+  else
+    return 8;
+}
+
+// Allocate memory for lf row synchronization
+void vp9_loop_filter_alloc(VP9_COMMON *cm, VP9LfSync *lf_sync, int rows,
+                           int width) {
+#if CONFIG_MULTITHREAD
+  int i;
+
+  CHECK_MEM_ERROR(cm, lf_sync->mutex_,
+                  vpx_malloc(sizeof(*lf_sync->mutex_) * rows));
+  for (i = 0; i < rows; ++i) {
+    pthread_mutex_init(&lf_sync->mutex_[i], NULL);
+  }
+
+  CHECK_MEM_ERROR(cm, lf_sync->cond_,
+                  vpx_malloc(sizeof(*lf_sync->cond_) * rows));
+  for (i = 0; i < rows; ++i) {
+    pthread_cond_init(&lf_sync->cond_[i], NULL);
+  }
+#endif  // CONFIG_MULTITHREAD
+
+  CHECK_MEM_ERROR(cm, lf_sync->cur_sb_col,
+                  vpx_malloc(sizeof(*lf_sync->cur_sb_col) * rows));
+
+  // Set up nsync.
+  lf_sync->sync_range = get_sync_range(width);
+}
+
+// Deallocate lf synchronization related mutex and data
+void vp9_loop_filter_dealloc(VP9LfSync *lf_sync, int rows) {
+#if CONFIG_MULTITHREAD
+  if (lf_sync != NULL) {
+    int i;
+
+    if (lf_sync->mutex_ != NULL) {
+      for (i = 0; i < rows; ++i) {
+        pthread_mutex_destroy(&lf_sync->mutex_[i]);
+      }
+      vpx_free(lf_sync->mutex_);
+    }
+    if (lf_sync->cond_ != NULL) {
+      for (i = 0; i < rows; ++i) {
+        pthread_cond_destroy(&lf_sync->cond_[i]);
+      }
+      vpx_free(lf_sync->cond_);
+    }
+
+    vpx_free(lf_sync->cur_sb_col);
+    // clear the structure as the source of this call may be a resize in which
+    // case this call will be followed by an _alloc() which may fail.
+    vpx_memset(lf_sync, 0, sizeof(*lf_sync));
+  }
+#else
+  (void)rows;
+  if (lf_sync != NULL) {
+    vpx_free(lf_sync->cur_sb_col);
+    vpx_memset(lf_sync, 0, sizeof(*lf_sync));
+  }
+#endif  // CONFIG_MULTITHREAD
+}